Electric drill.



3 BHEETS-SHEET 1.

Patented 0@1..12,19o9.

ELBGTRIG DRILL.

APPLIUATION FILED MAY a, 1905.

Wi 0. DUNTLEY L H. J. KMMAN.

ELECTRIC DRILL.

APPLIOATION FILED MAY a, 1905.

@36pm/QQ Patented not. 12,1909.

3 SHEETS-SHEET 2.

. O yfssfs.- 71( 7 7 74 /NvE/vofes F y v Y n y r @y @WM :7M/1 NORA/EnsW. 0. DUNTLEY L H. J. KIMMAN. BLEGTRIG DRILL.

APPLICATION FILED MAY s, 1905.

9861,87@ l Patented Oct. 12, 1909.

3 SHEETS-SHEET 3.

.7429 AHORA/Ens currar) STATES PATENT carica.

WILLIAM 0.` DUNTLEY,OF CHICAGO, ILLINOIS, AND HRY J. KIMMAN, OIE CLEVE-LAND,

JERSEY. l

l To all whom it mcy-concern:

` Y. is to produce an etiicient and reliable tool or drill of `thischaracter, chierI among whose advantageous features is a provision forpreventing 'overloading of the drill, the result being accomplished,inthe present instance,

by so constructing and arranging the driving connection between theiiiotor and the tool spindle that such connection is renderedinoperative -whenthe drill `becomes overloaded, With the. result thatthe drill is `stopped without interfering with or stopping the electricmotor, which continues to run Without effect upon` the tool spindle ordrill.

Our invention relates, to other -advanta-l geous features,'such as anovel and original` construction of switch device for the motorjcir'cuit, aswell as a novel and original form ,f of force feed devicefor the tool or machine.

In lthe d rawings,'ld`igure 1 is a longitudil nal sectional elevationoii7 an electric vdrill embodying our'invention'; Fig. 2 a plan viewthereof; F lgs. 3 and 4 details of the switch;

Figa 5 an elev-ation of the brush holder, and

Figs. 6 and 7 sectional views yillustrating :modified vforms of gearing.

xfReferring to the particular embodimentof *our invention as hereinillustrated. the elec- 'I tric drill comprises a main casing' 1. withinwhich is'arranged an-electric motor 2, the

, lcasing "preferably forming the Aiield frame of such motor.

i Moreover, by preference, tlie casing is providednwith a series oftianges lor ribs 3, for the purpose lof'lradiatng the heat. that maypossibly be generated and to assist the fan device -in'co'oling `themotor, as hereinafter described; lBy preference, the upper portion oftiie'casin'g is substantially cylindrical, but is outwardly'flared atits lower e "end andprovided at itsextreme end with a Range-4, in orderthat the gear casing 5 may specification of 'Letters Patent.

-ing a Morse taper.

OHIO, 1ASSIGNORS,I BY DIRECT `ANB MESNE ASSIGNMENTS, TO CHICAGOPNEUMATIC TOOL COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION 0F NEW'Vnimse'rme imiLL.

Patented Oct. 12, 1909.

a, i905. serial no. 258,675.

be secured to the main casing of the machine or drill. Between this maincasing and the gear casing is clampeda lower head or diaphragm 6, inlwhich is arranged the lower bearing 'i' of the armature shaft 8 of theelectric in otor, which bea-ring may be of suit.- able construction, butherein showneas a ball bearing.y Anotherhead 9 is arranged at the upperend of the main casing of the machine and the saine is in the presentinstance and 'by preference, east or formed integral with the main casinrllhis upper head is provided witli a suitable bearing 10, in thepresent inst-ance a ball bearing, for the purpose of journaling theupper end of .the armature shaft. The lower end of the armature shaftextends through its bearing and through the diaphragm or lower head 6and is formed as or provided with a pinion 11, which lis ar-I ranged tomesh with a train of gears, Jfor the purpose of transmitting the motionor rotations ot' the armature to the tool socket or spindle 12, whichreceives theshank of.

the drill or other working tool in the well f known manner. ln' thepresent instance, the

particular forni of gearing employed and' herein `illustrated is of theplanetary type comprising essentially two gears or pinioiis 13 revolvingin connection with a circular rack 14. arranged in asocket in the upperend of thejgear casing. These revolving gears are mounted torotate-freely on the vertical studsl, which are in turn secured upon therevolving yoke or gear frame 16 pinned or otherwise secured to the toolspindle .12. lu the present instance, this tool spigdle is provided witha tool socket 17 hav- As illustrated in Fig. 1 the revolving gearsproperdo not-(imesh with the circular rack 14, but the saine areprovided with hubs 18 formed as pinions for directly engaging with thecircular rack 11i.

it will be understood that if the machine or drill should be constructedas just described, the same is liable to be overloaded from severalcauses, such its the use of a drill -largertl'ianl the capacity or powerot the machine, o-r by too great pressure or feed eX- erted on the toolor drill, with the result that owing to the consequent stoppage orslowing down ot the electric motor, the latter would be supplied withsuch an amount/oi/ out the armature windings. To overcome this objectionof overloading, preferably without interfering with the motor o1' itscurrent, is the principal feature of our present invention and toaccomplish this result, we provide means whereby the gearing becomesinoperative when the load on the working tool reaches or exceeds apredetermined amount. In the present instance, this result is broughtabout through the medium of the circular rack 14, which is nor- 'mallyin a fixed or stationary position so long as the predetermined load 1snot reached orv exceeded, but which is adapted -to slip Within itssocket in the casing, whenever such predetermined load is reached orexceeded. In the normal operation the circular rack is in fixedpositlon, as stated, and the revolving gears 13 are consequently enabledto transmit the motion of the motor to the tool spindle, but obviouslywhen the predetermined amount of load is reached or exceeded andjincreased pressure brought to bear by thefv revolving gears or pinionsagainst the rack the latter will slip and be rotated, withthe resultthat the tool spindle will stop, while theelectric motor will continueto run. In the present instance, the

. driving connection between the tool spindle and themotor may beconsidered a frictinal drive in connection with gearing, the arrangementbeing such as hereinafter described, that the amount of friction orfrictional resistance may be adjusted in degree at the will of theoperator, so that the predetermined amount of load may be varied'asdescribed.

Referring to the construction as herein illustrated, the circular rack14 coperates with means for applying pressure or frictional resistancethereto, such means comprisin a pressure applying ring 19, arrangetheretoward with yielding pressure by means of a series of springpressed studs 20. Each of these studs projects upwardly through theupper end of a spring case 21 formed on the gear casing and containing aspring 22 ressing against the head of the stud 20 an also against a nut23 arranged to screw upon the spring case for the purpose of varying oradjusting the tension of the spring and` consequently varying oradjusting the amount of the frictional resistance of the curved'rack 14.In order to receive the upward thrust on the circular rack we'provide anabutment 24, which is in theforin of a ring secured to the gear -casing.By preference, we provide 'between the rack 14 and the two rings 19 and24, resistance rin 25 of suitable material such as fiber.

vide a proper and uniform amount of resistance, and moreover cannot becrushed or become cut. The load which can safely be below the circularrack and held e'prefer to employv these fiber rings, inasmuch as thesame pro-' amount of load is still carried by it, because of the factthat it is at Such time, rotating the rack on which the frictionalresistance is constant. Consequently, the motor carries thepredetermined amount of load, but is relieved of the excess load.

IVe do not limit our invention to the speciic character ofgearingillustrated in Fig.l

l, nor to the specific manner or meansfor obtaining the resultshereinbefore referred to, inasmuch as the same results could beaccomplished by other specific means without departing from the spiritof our invention, and

vrun wild, inasmuch as the predetermined furthermore, our invention isapplicable in respect to other constructions of gearing, as

illustrated in Figs. 6 and 7 hereinafter described.

Referring next to the switch device, as

`V,illustrated 1n general in Fig. 1 and inl detail in y.Figs 3 and 4,the same comprises two sprl terminals26 arranged in the motor circuitand supported by the insulating block 27, fastened, 1n the presentinstance, on the upper surface of the lower head lor diaphragm' 6. Theconnection between these terminals is under thecontrol of two keys orbuttons 28 and 29, which are arranged to project from Athe upper surfaceof an extension 30 of the main casing and on either 'side of one of thegrasping handles 31, which, as indicated in` Fig. l, is secured into oneside of the main casin The lower end of the button .29 is provided withmeans for electrically connecting the two terminals and, in the presentinstance, such means consilsts of an anti-friction roller 32 ofconducting material, with the result that when the button 28 is in itsinnermost position, as illustratedin Fig. 4, the motor circuit isclosed,

the other button 29 being at this time in its outermost position. Forthe 'purpose of holding the buttons with a yielding pressure inoneposit-ion or the other, we provide suit able means such as the lever 33,rocking on the axis 34 intermediate its length with its ends bearing inand engaging the side recesses 35 and 36'of the buttons 28 and 29,respectively. This lever is provided with al depending larm or finger37, in whose path of movement is interposed the double bevv. eled orwedge-shaped end or head ofan uping the buttons in their relativeposition, to

which they have just been moved. The result of this movement of thebuttons is to open the circuit by removing the roller 32 from itscooperative relationship with the terminals. By preference, the buttons28 and 29 which, as indicated in Fig. 4, have their bearings in the topof the extension 30 and also through the two lugs 4() and 41tlierewithin, are arranged or disposed in a plane parallel to thearmature shaft and ooni sequently to the line of thrust vwhich isdirectly along the central axis of the tool or machine and through theaxis of the tool spindle. movable elements of this switch, that is thebuttons, is in the direction of the longitudi- 'iial axis of the machineor drill and transverse to the longitudinal axis of the handles, withthe result that the switch may be operated aiid/ the drill therebycontrolled without disturbing the position thereof with relation to thework, which might otherwise result when the tool is held simply by thegrasping hands. Moreover, the buttons are arranged on either side of thehandle so as to be easily controlled by the operator.

Referring next to the force feed device, the same comprises, iii thepresent instance, a yoke or U-shaped frame 42, whose parallel membersare screw-threaded on their outer edges and enter the interior of themain casing through the top thereof. The cross piece of' this yokeextends diametrically across the top of the machine` or drill Aand is vprovided at a' point coincident with the longitudinal axis or line ofthrust of the machine or drill, with a centering point 43. For thepurpose of operating the yoke and thereby changing its position withrelation to the main casing to bring about a force feed,

we provide a pilot wheel 44 internally screwthreaded to engage thescrew-threaded arms or members of the yoke 42, the yoke being moved upor down, that is in or out with respect to the main casing accordinglyas the -ivheel is moved iii one direction or the other.-

For the purpose of maintaining the .pilot wheelin fixed posit-ion withrespectrto the longitudinal axis of the tool or machine, we provide aretaining ring or cap 45, which is secured in suitable manner to theupper surface of the end head 9, which projects above the top plane ofthe main casing proper, the wheel operating between such ruig. or cap 45rlhe direction of movement of the.

and such to plane or edge of the main casing, as clear y indicated inFig. 1. This construction not only provides an efficient and serviceableforce feed device, but also serves as a grasping handle when the yoke ismoved outwardly sufficient to permit the hand of the operator to graspthe cross piece of the yoke, such grasping handle, or rather the socalled grip, being advantageous, especially inv `reaming. opera-tionsand where it is desirable that the operator shall hold the tool by oneof the regular handles and also by a grip which is in a differentposition or location than -the other regular grasping handle of themachine. y

'As illustrated in F 1, the machine or drill may be provid with twograsping handles, the handle 31 already described, and also the handle46, through the latter of which the leading-in wires or cable 47 of themotor circuit may be passed. As seen in Fig. 1, these wires connect witha fuse 48 which 1s arranged opposite one of the openings 49 in theoutwardly flared portion of the main casing. 1, with the result that thefuse may be easily and conveniently removed and a new one substituted.rlhese openings 49, how- .I

- ever, are primarily air ports for the passage' of air and the samecoperate with a fan device for forcing a circulation of air through thecasing and among the elements or inembers of the motor, that is to say,our motor is air cooled. Asherein shown, thefan 5() is secured to thelower bearing 51 on the arma.- ture shaft 8. The openings 49 are for theentrance or exit of the air accordingly as the `blades of the fan are sopositioned as to force -or draw the air through the motor casing.

The gear casing is by preference partially or wholly illed with asuitable lubricant, desirably a heavy oil or a so called compressiongrease, or the like,'and for the purpose of introducing such lubricantwithin the gear casing,1 provide one or more openings closed by screwplugs 5a.

As hereinbefore suggested, the type of gearing in which my invention maybe embodied may partake of differentv forms, as illustrated in Figs. 6and 7. Referring first to the modification of Fig. 6, the armaturepinion is operatively connected, as heretofore, with revolving pinions,butyin the present instance, such pinioiis marked 52 directly gengage ormesh with the rack 53, instead of being operatively connected therewith,throu h pinions ontheir hubs,;a s in Fig. 1. In this modification,the-retaining ring 24 is dispensed with and the upper friction ring 25vis clamped between the head or diaphragm 6 and Vthe upper edge of therack. In other respects, the construction and mode of operation issubstantially the same as the device illustrated in Fig. 1. Referringnext to the second modification illustrated in Fig.v

-7, the armature pinion meshes withl the two revolving pinions 54, whichengage a permanently fixed circular rack 55 secured in a socket on thelower edge of the diaphragm 6. These revolving pinions rotate freely onstuds 56, secured in the yoke 57, whose hub is journaled on the upwardextension 58 of the tool spindle. rllhis hub is formed as a pinion 59engaging the two `revolving pinions 60 mounted on the studs 6l of therevolving yoke 62, which is directly fastened or keyed to the toolspindle. rlhese revolving pinions 60 mesh with the circular rack 63,which is provided with the friction rings 64, arranged at the oppositeedges thereof. The tensionapplying ring presses against the upper edgeof the rack and is held theretoward by means of the spring pressed studs66. rllhese studs are arranged in a case 67 formed in the diaphragm orhead 6, in which screws the nut 68, for the purpose of adjustinvr theten sion of the spring 69 therewithin. lhis form of gearing, whichv maybe considered a double planetary type, operates in the same manner sotar as the result .of preventing overloading is concerned. i

rlhe brush holder in the present instance I is constructed asillustrated in Fig. 5, which provides a sim le arrangement, althoughother forms of crush holders may be employed. The brush holder comprisesessentially a plate 70 secured to the upper head or end plate of thecasing and having anl eX- tension (1 provided with an opening to receivethe brush (2, which is forced head on against lthe commutator 73 of themotor, with a yielding resistance by mea-ns of the two liat springs 74,whose ends are fastened in the posts 75 rising from the plate 70.

We claim:

l. In an electric. drill, the combination, with an electric motor and atool spindle, of a train of gearing between said motor and tool spindle,oneof the members of the train being a rack normally stationary. butarranged to rotate and thereby destroy the operating connections betweenthe motor and tool spindle when the load oni the latter reaches apredetermined amount.

2. In an electric drill, the combination,

`with an electric motor and. a'tool spindle, ofplanetary gearing formingthe operat1ng` connection between the motor and spindle,

one member of the train being arranged. to

become inoperative when the load reaches a predetermined amount.

3. In an electric drill,.the combination, with an electric motor andatool spindle, of planetary gearinglforming the operating connectionbetween the motor and splndle, and comprising a rack and pinions, saidrack being normally stationary but arranged to rotate when the .load `onthe tool splndle reaches a predetermined amount.

4. In an electric drill, the combination,y

amount to resist a @saam ot planetary gearing forming the operatingconnection between the motor and spindle and comprising a rack andpinions, and a casing or support with which said rack has rictionalre'slstance up to a predetermined equaling the rictional resistance withsaid ring.

6. ln an electric drill, 'the combination, with an electric motor and atool spindle, of planetary gearing forming the operating connectionbetween the motor and spindle predetermined load on they and comprisinga curved rack and pinions,

and means for clamping said rack to resist a predetermined'load onthetool spindle.

hln an electric drill, the combination, with an electric motor and atool spindle, oi. planetary gearing forming the operating connectionbetween the motor and spindle and comprising a rack and pinions, and

means for imparting a predetermined iricl tional resistance to the rackto resist a predetermined load on the tool spindle.

8. ln an electric drill, the combination, with an electric motor and atool spindle, of train of gearing orming the operating connectionbetween the motor and spindle, one of the members of the train being arack, and means for imparting to the rack a resistance adjustable indegree.

9. lin an electric drill, the combination, with an electric motor-and atool spindle, of planetary gearing forming the operating connectionbetween the motor` and spindle, one of the members of the train being arack, andm'eans for im arting thereto a frictional resistance adjusta lein degree to resist any predetermined load on the tool spindle.

10. In an electric drill, the combination, with an electric motor and atool spindle, of planetary gearing forming the operating connectionbetween -the motor and spindle and comprising a rack and pinions andspringsv impartmg ayfrictional resistance to the rack. 11.

11. In an electric lthe combination, with an electricy motor anda toolspindle, of, planetary gearin'gvformi'ng the operating connectionbetween' the'motor. and spindle and comprising a rack and pinions, sprins imparting a frictional resistance to the ra vvarying the tertsionv ofthe and .means for sprmgs.

12. In an electric with anelectric motor and a tool spindle, of

drill, ,the combination,

v ovith an elec-tric motor and a tool spindle, of

planetary gearing forming'the operating connection between the motorand'spindle and comprising a lrack and pinions, a friction ring bearingagainst the rackv and a series of spring-pressed studs bearing j againstthe ring to hold the rack with a predetermined frictional reslstance.

15. In an electric drill, the combination,

with an electric motor and a tool spindle, of

planetary gearing forming theA operating connection between the motorand spindle andcomprising a rack and' pinions, a friction ring. bearingagainst the rack, a series of spring-pressed studs bearing against thering to hold the rack with a frictional resistance, and means foradjusting the degree of tension exerted by such studs.

16. In an electric drill, the combination,-

with an electric motor and a tool spindle, of planetary gearing formingthe 'operating connection between themotor and spindle and comprising arack and pinions, a casing or support having a socket to receive suchrack, and means for holding said rack therein .with an adjustablefrictional resistance.

17. In an electric drill, the combination,

with a casing and with the electric motor armature arranged therein, ofa fan within the casing which is provided with openings for the passageof air, and fuse arranged 1n the electric motor circuit and locatedadjacent one of said openings for ready inspection and replacement.

18. In an electric drill,'the combination,

with'a casing and with the electric motorarmature arranged therein, of aforce feed device comprising a screw-threaded yoke, and a screw-threadedwheel or ring engaging said yoke and bearingagainst the casing. 19. Inan electric drill, the combination, with a casing and with the electricmotor armature'arranged therein, of a force feed device comprising ayoke whose parallel members are screw-threadedl and enter the casing,and a screw-threaded ring engaging said yoke and bearing against thecasing.

20.111 an electricdrill, the combination,

, with a casing and .with the` electric motor armature arranged therein,of a force feedv device-comprising a U-shaped frame whose.

to its normal position.

parallel screw-threaded members enter the casing and whose cross-pieceextends diametrically across the outer end of the casing, and ascrew-threaded ring engaging `said yoke and bearing against the casing.

21. In an electric drill, the combination, with a casing and with theelectric motor armature arranged therein, of a force feed devicecomprising a yoke whose parallel members are screwthreaded and enter thecasing, said yoke having al centering point, anda screw-threaded ring orwheel engaging said yoke and bearing against the casing.

22. In'an electric drill, the combination, with a casing and with theelectric motor armature arranged therein, of a force feed devicecomprising a screw-threaded yoke, and a screw-threaded wheel engagingsaid yoke and rotatably mounted on the casing and having a fixedrelation thereto with respect to the longitudinal axis thereof.

Q3. In an electric drill, the combination, with the casing and the motorarmature therein, -of an electric switch for controlling I said motor,and grasping handles connected 'with the casing, said switch havingcontact parts within said casing and an actuating part on the outsidethereof adjacent a handle and within reach of the operators hand.

24. In an electric drill, the combination with the casing and the motorarmature therein, of grasping handles on the casing, an

elect-ric switch for controlling said motor,

said switch comprising Contact parts within said casing, a button foroperating said contact parts, and another button for restoring saidparts to their normal condition, said buttons projecting through thecasing to the ilitside thereof and adjacent one of .the han- 25. Thecombination with an electric drill, of grasping handles on the-casing, acontrolling switch. therefor, said switch being mounted upon said drill,and comprising contact parts, a part adapted to be inovedto operate saidcontact parts, and a part adapted to be moved to restore' said operatingpart 26.111' an electric drill, the combination with the casing, and themotor therein, of a handleon said casing, and a switch for controllingsaid motor, said switch being mounted on saidvcasing, and having twoactuating parts, one located on either side of said` handle.

27. In an electric drill, the combination with `the casing, and themotor therein, of a handle-secured on said casing, and a switch forcont-rolling said motor, said switch being mounted on said 'casing andhaving an operating button, and a. restoring button, said buttons beingarranged for movement in the direction ofthe longitudinal axis of thedrill, and being located one on either side of said handle. V

'rection of the longitudinal axis of the motor,

whereby the drill may be controlled Without disturbing its position withrelation to thei AQwork.

Q9. In aii electric drill, the combination (with the casing and themotor therein, of a handle secured to the outside of the casing, andanelectric switch for controlling said motor, said switch having itscontactparts within said casing, and its actuating part or buttonprojecting through the caslng in proximity to said handle, said buttonbeing movable substantially in the direction of the line of thrust ofthe drill.

30. In an electric drill, thecombination with the casing and the motortherein, of a handle secured to the casing, and an electric switch forcontrolling said motor, said switch comprising contact parts within saidcasing and an actuating part outside of said casing in proximity to saidhandle, said `iactuating part being so disposed/as to require a movementtransverse to the longitudinal axis of said handle to actuate the same.31. In an electric drill, the combination with the casing'and the motortherein, of an electric switch for controlling said motor, said switchcomprising'contactparts and an actuating part, s/aid actuating partbeing located upon the outside of said casing and being so disposed asto require a movement thereof inthe direction of the longitudinal axisof the motor to operate the switch.

32. In an electric drill, the combinatioir with the casing, and themotory therein, of

a handle secured to the outside of said cas-- ing, an electric switchfor controllin the circuit of saidlmotor, said switch eing mounted onsaid casing and having two actu ating parts arranged in proximity tosaid handle, said arts being movable substantially in the direction of-the line of thrust of the drill,'one of said actuating partsy operatingto make the circuit and the other' to break the circuit. p

33. In an 'electric drill, the combination with the casing, and themotor therein, rof a handle secured to the outside of said casing, anelectric switch for. controlling the circuit of saidmotor, contact partsfor said switch within said casing, and actuating parts for said switchprojecting through,

said casing in proximity tosaid handle, said actuating parts beingdisposed one on either side of said handle and being arranged to beessere moved in the kdirection 34. 'In an electric drill, thecdrnbination with a casin and a motor therein, of two handles rigid ysecured to the outside of said casing at diametrically opposite points,and an electric switch for controlling said motor, said switchcomprising contact parts located within said casing,` an actuating keyor button coperating with said contact parts, a restoring key or button,and a link connecting said buttons projecting through said casing inproximity to said handle and being so disposed with relation to thedrill that their operating movement is in the direction of thelongitudinal axis thereof.

35. In an electric drill, the combination with the casing and the motortherein, of a handlesecured on said casing, and a switch or controllingsaid motor, said switch being mounted on said casing, and having anoperating button, a restoring button, said buttons being movable in thedirection of the line of thrust of the drill, and means for holding thebuttons in one position or the other with a yielding pressure.

36. 'In an electric drill, the combination for controlling said motor,said switch being mounted on said casing, and having an operatingbutton, a restoring button, said buttonsbeing movable in the directionof the line of thrust of the drill, and a springpressed pin. cooperatingwith said buttons to hold them in one position o1' the other.

37. In an electric drill, the combination with the casing and the motortherein, of a handle secured on said casing, and a switch forcontrolling said. motor, said switch being mounted on said casing, and'having an operating button, a restoring button, a connecting rockinglever between-the buttons having a projecting finger, and a spring'-pressed pin coperating with said finger to hold' the lever and thebuttons in one position or the other, said buttons being movable in thedirection of the line of thrust of the drill.

y WILLIAM O. DUNTLEY. .HENRY J. KIMMAN.

Witnesses to the signature of William O.

Duntley:

' S. E. HIBBEN, H' GERTRUDE C. ARMSTRONG. Witnesses to the signature ofHenry J. Kimman: i

J. MILLS, S. R. WALLACE.

looI

